ACl Rod bearing question

[krashdumie05]

nope 0.25mm = 0.010"

OP what is the P/N on the packet?

Pn i got is 6B1569HX-STD. The .025mm or .001. was recomended by a shop that deals primarily with e46 m3s (they are a shop that people have head on the forums). The extra clearance was recomended based on my usage

[digger]

Pn i got is 6B1569HX-STD. The .025mm or .001. was recomended by a shop that deals primarily with e46 m3s (they are a shop that people have head on the forums). The extra clearance was recomended based on my usage

OK so its not 0.25mm atleast that's been established.

With things like this always measure and go based on actual measurements with the stock size first off as with everything there is a range of values, and deal with what is in front of you.

0.001" extra is more than likely too much additional clearance unless yours are well and truly on the tight side

[krashdumie05]

Thanks for the help. Do you know where I can find the clearance specs?

[Syfon]

And, to head off your next question, ARP rod bolts are also a downgrade from stock. Less round bore and less clamping force.

Problem is, if OP has an lci variant with non-reusable rod bolts, and he wants to plastigauge each journal, he'll need 2 x sets of oe rod bolts as they're single use only.

I used ARP rod bolts in mine. Torqued to spec as per ARP's recommendations along with their fastener assembly lube (I don't have a stretch gaue). No problems on my end.

The whole thing about ARP rod bolts not providing adequate clamping force is nothing but a myth. Yes they may provide less than OE rod bolt clamping force, but it's clearly a negligible amount. Otherwise we'd have seen numerous S54 failures solely attributed to ARP rod bolts and their lesser clamping force.

ARP rod bolts are fine so long as their torqued to spec per ARP AND their fastener assembly lube is utilised.

Furthermore - for anyone wanting to use ARP rod bolts in their LCI S54 (i.e. M10 rod bolts), the correct part number is 201-6102. S50B30 M10 ARP rod bolts are correct for LCI S54's with M10 bolts.

https://arp-bolts.com/kits/arpkit-de...?RecordID=1108

[Syfon]

OP FYI - I have ARP main & rod bearings in mine.

Rod bearing P/N is 6B1569H - .25

My crank was machined so oversize were correctly chosen / installed.

[dutchhome]

I used the ARP bolts on my 2001 but used a stretch gauge rather than going based on torque. I did try the torque technique first and measured stretch afterwards and I found the stretch to be very inconsistent. Based on this experience and because ARP recommends using a stretch gauge I decided stretch alone was the better technique.

Regardless of what is chosen, oil analysis should detect early wear before it becomes a problem as long as everything was installed properly.

[digger]

Thanks for the help. Do you know where I can find the clearance specs?

i found this

http://www.adkusters.dsmynas.com/Web.../11_24_571.pdf

0.040mm to 0.070mm (0.0016" to 0.0028")

or as a second source

http://wiki.rcollins.org/core/index....4_Rod_Bearings

Bearing Clearance Variance

0.0361 - 0.0660 mm

0.00142 - 0.00260 inch

[Anri]

Yeah, extra clearance on the s54 is a reliability downgrade. Avoid.

Could you explain in details why is down grade ?

[S54B32]

Problem is, if OP has an lci variant with non-reusable rod bolts, and he wants to plastigauge each journal, he'll need 2 x sets of oe rod bolts as they're single use only.

I used ARP rod bolts in mine. Torqued to spec as per ARP's recommendations along with their fastener assembly lube (I don't have a stretch gaue). No problems on my end.

The whole thing about ARP rod bolts not providing adequate clamping force is nothing but a myth. Yes they may provide less than OE rod bolt clamping force, but it's clearly a negligible amount. Otherwise we'd have seen numerous S54 failures solely attributed to ARP rod bolts and their lesser clamping force.

ARP rod bolts are fine so long as their torqued to spec per ARP AND their fastener assembly lube is utilised.

Furthermore - for anyone wanting to use ARP rod bolts in their LCI S54 (i.e. M10 rod bolts), the correct part number is 201-6102. S50B30 M10 ARP rod bolts are correct for LCI S54's with M10 bolts.

https://arp-bolts.com/kits/arpkit-de...?RecordID=1108

Sorry but that is total wrong! Original bmw rodbolts (m10x1.25 for „Facelift“ s54) need to be tighten to spec at least 3 times to achieve full clamping force / max tensile strength. But not more than 5 times. You can read this in the official bmw manual for shops (newtis, Ista-D or BMW AiR)

correct way to tighten them down is:
application torque: 5nm
joining torque: 30nm
angle of rotation: 105°

then loosen and repeat this (all together 3 times at least)

@anri: My oilpressure NEVER get lower than 1.5bar at very hot idle. Even after some laps on track. I‘m on full std oilpump, crank and std ACL bearings.


Bmw documents say: clearance 0,030-0,070mm with plastigauge measuring method.

[krashdumie05]

FYI. After speaking with acl they gave me some good information. They typically run the hx std on a stock unmachined crank

They said that based on my usage (8 de events / year) , they would run the HX-std but I would need to be mindfull of oil starvation at higher rms.

It was their recommendation that I either run the HX std and reduce my rpm limit or increase sump and or install higher volume pump

Their other option is to run the h-std and just check for clearance.

I have martyns tool so I can reduce rpm limit easily

Im leaning towards running HXStd and reducing the rpm to 7000 as I rarely go to the limit even at the track

oh and yes I'm using the arp bolts. I have installed them on another s54 with no problems after 1k track miles. I'll be using them on my build.

[Obioban]

FYI. After speaking with acl they gave me some good information. They typically run the hx std on a stock unmachined crank

They said that based on my usage (8 de events / year) , they would run the HX-std but I would need to be mindfull of oil starvation at higher rms.

It was their recommendation that I either run the HX std and reduce my rpm limit or increase sump and or install higher volume pump

Their other option is to run the h-std and just check for clearance.

I have martyns tool so I can reduce rpm limit easily

Im leaning towards running HXStd and reducing the rpm to 7000 as I rarely go to the limit even at the track

oh and yes I'm using the arp bolts. I have installed them on another s54 with no problems after 1k track miles. I'll be using them on my build.

I can't decide if this post is a parody or serious. S54 not going over 7000rpm on track?

Anyway, back to tracking my 160,000 mile M3 with 8300rpm redline, shifted at 8000+ RPM for every shift of it's 20,000+ track miles.
(second set of OE rod bearings/bolts).

[bigjae46]

Anyway, back to tracking my 160,000 mile M3 with 8300rpm redline, shifted at 8000+ RPM for every shift of it's 20,000+ track miles.
(second set of OE rod bearings/bolts).

I prefer this bearing issue vs seeing the issues other cars have on track.

Not sure I’d consider the bearings to be a problem. More of a maintenance item on a high performance motor. If you consider the maintenance requirements on the older S engines then rod bearings and valve adjustments don’t seem so bad.


Sent from my iPhone using Tapatalk

[krashdumie05]

Contacted a few places to see what they recomended.

Lang racing. H-STD
rogue engineering. HX-STD no concern with rpm
Morehead speed works H-STD
FCP. HX-STD
VAC H-std although they don't sell them

[Syfon]

Sorry but that is total wrong! Original bmw rodbolts (m10x1.25 for „Facelift“ s54) need to be tighten to spec at least 3 times to achieve full clamping force / max tensile strength. But not more than 5 times. You can read this in the official bmw manual for shops (newtis, Ista-D or BMW AiR)

correct way to tighten them down is:
application torque: 5nm
joining torque: 30nm
angle of rotation: 105°

then loosen and repeat this (all together 3 times at least)

@anri: My oilpressure NEVER get lower than 1.5bar at very hot idle. Even after some laps on track. I‘m on full std oilpump, crank and std ACL bearings.


Bmw documents say: clearance 0,030-0,070mm with plastigauge measuring method.

BMW state the M10 rod bolts must not be reused?

I've never read anywhere they can be reused albeit not more than 5 times?

Mine was never opened (to my knowledge), yet I didn't reuse the stock m10 rod bolts. I went with arp rod bolts.

My post stated that the whole thing regarding arp rod bolts not providing sufficient clamping force may be true, however the clamping force differential would be miniscule, otherwise by now, we would have seen many s54's with arp rod bolts having failed where the failure could be directly and solely attributed to the arp rod bolts and their insufficient clamping force. Many people I know have built s54's with arp rod bolts (installed by torqueing to spec, and not by stretching), and they haven't failed after many thousand km's of hard street and track driving.

[Obioban]

Problem is, if OP has an lci variant with non-reusable rod bolts, and he wants to plastigauge each journal, he'll need 2 x sets of oe rod bolts as they're single use only.

I used ARP rod bolts in mine. Torqued to spec as per ARP's recommendations along with their fastener assembly lube (I don't have a stretch gaue). No problems on my end.

The whole thing about ARP rod bolts not providing adequate clamping force is nothing but a myth. Yes they may provide less than OE rod bolt clamping force, but it's clearly a negligible amount. Otherwise we'd have seen numerous S54 failures solely attributed to ARP rod bolts and their lesser clamping force.

ARP rod bolts are fine so long as their torqued to spec per ARP AND their fastener assembly lube is utilised.

Furthermore - for anyone wanting to use ARP rod bolts in their LCI S54 (i.e. M10 rod bolts), the correct part number is 201-6102. S50B30 M10 ARP rod bolts are correct for LCI S54's with M10 bolts.

https://arp-bolts.com/kits/arpkit-de...?RecordID=1108

You can plastigauge with stock bolts.

I don’t think I’ve seen anyone say the ARPs provide insufficient clamping force— just that they provide less clamping force (and a less round bore than ARP bolts torqued to their spec with their lube). The Oe bolts are also cheaper.

AKA. The ARPs are fine. But, the OE’s are cheaper, stronger, and rounder result, at the cost of marginally more effort to the job. Seems like an easy enough choice to me.